Air operated projectile firing apparatus

ABSTRACT

There is herein disclosed caseless ammunition having a rigid solid self-supporting porous propellant ignitable by surface contact with high temperature air and methods of making such a propellant with controlled porosity to provide predetermined ignition and propulsion characteristics.

United States Patent [72] Inventors William Harold Batie;

Glenn Clark Smith; Robert Keith Marshall,

Rogers, Arkansas [21] Appl. No. 683,029

[22] Filed Nov. 14,1967

Continuation of Ser. No. 469,987, July 7, 1965 [45] Patented Sept. 29,1970 By mesne assignments to Victor Comptometer Corporation, Chicago,Illinois a corporation of Illinois.

[73] Assignee [54] AIR OPERATED PROJECTILE FIRING APPARATUS 3 Claims, 2Drawing Figs.

[52] U.S.Cl 89/7,42/l, 102/38,137/S33.11 [51] lnt.Cl F4lfl/04 [50] Fieldof Search 89/7; IOZ/CD; 42/1; 137/531] 1, 533.l3,.533.l7, 533.19, 519.5

[56] References Cited UNITED STATES PATENTS 1,764,186 6/1930 Teesdale137/533.15X 2,591,174 4/1952 Martin..... 137/533113 3,064,381 11/1962Uilbajo 42/1(.2)UX FOREIGN PATENTS 1,321,746 2/1963 France 102/(C.D.)UX

Primary ExaminerSamuel W. Engle Altorney- Harness, Dickey and PierceABSTRACT: There is herein disclosed an air ignition system firearmwherein a ball valve is freely floatingly mounted in a valve chamber ina separate one-piece valve plug mounted on the front of an axiallymovable air compression device.

Patented Sept. 29, 1970 3,530,762

4 7 I INVENIORS, 70 267 155% f 6/0 7171 6', 67772??? ran/5K4.

AIR OPERATED PROJECTILE FIRING APPARATUS This is a continuation ofapplication Ser. No. 469,987, filed July 7, 1965, now abandoned.

This invention relates to air operated projectile firing apparatus ofthe type adapted to utilize ammunition having a projectile portion andan associated propellant portion capable of being ignited by surfacecontact with high temperature air.

This invention is related to and adapted to be utilized with apparatusof the type disclosed in copending application Ser. No. 473.556 filedJuly 7, 1965, for Air Operated Projectile Firing Apparatus.

The objects and advantages of the invention have been attained byutilization of the inventive principles disclosed hereinafter byreference to the accompanying drawing in which:

FIG. 1 is a side elevational view, in section, of a projectile firingdevice having a new and improved valve assembly; and

FIG. 2 is an end view ofthe valve assembly.

In general, the invention is in the provision of a new and improvedvalve assembly in apparatus for firing projectiles which iseharacterizedby the provision of a valve chamber adapted to floatinglyreceive a valve member between afiring chamber in which a propellant isignitable by surface contact with'high temperature air andair'compression means for'obtaining the high temperature air, a valvemember floatingly mounted in the valve chamber for movement between anopen position permittingflow of high temperature air from the aircompression means to the firing chamber and a closed position preventingflow of high temperature high pressure gases from the firing chamber tothe air compression means after ignition of the propellant and forming arigid reaction wall therebetween, and retaining means floatinglyretaining said valve in said valve chamber.

Referring now to the drawing, barrel means l and a compression means 12are connected, in a firing position, by breech means 14. Ammunitionholding means 16 comprising a central bore 18 having stepped portions20, 22, 24 supports the ammunition 26 which has a propellant portion 27ignitable by surface contactwith high temperature air to drive theprojectile throughthe barrel. An obturating plug 28 of integralone-piece construction is mounted in a compression cylinder head 30 andsupports the valve assembly 32 in a central bore 34 which provides apassage having a longitudinally extending central axis connecting aircompression chamber 36 to firing chamber 38. Thefirst part of thepassage adjacent the compression chamber has a perimeter of reduceddiameter relative to the remainder of the passage.

The valve assembly 32 comprises valve means 40, in the form of a ballvalve, and valve seat means 42 in the form of a conical surface along asecond part of the passage next adjacent the reduced diameter'part andformed by an outwardly diverging surface. The valve seat is formed in arigid reaction wall 43 and faces away from the air compression chambertoward the firing chamber. A valve chamber 44 is formed in a third partof the passage next adjacent the valve seat by an enlarged cylindricalbore at the end of the valve seat. The valve chamber is larger than theball valve so as to floatingly support the valve. Retaining-means 46 areprovided at the end of the valve chamber 44. In the illustrativeembodiment, the retaining means comprises a one-piece coil springelement 48 compressible fixedly mounted in an enlarged retainer seat 50formed in a fourth part of the passage next adjacent the valve chamberand extending along the wall of the passage from the valve chamber tothe firing chamber and mounted to floatingly retain the valve betweenthe end of the retainer and the valve seat. It may be observed that thecoil spring element 48, in the illustrative embodiment. comprises alength of resilient spring sheet material wound into coil form,compressed, inserted into the valve chamber, and held therein byspring-like expansion forces. The width of the polygonal sheet materialis substantially equal to the length of the retainer seat. Passage means52 are thus provided through the retainer means to connect the firingchamber to the compression chamber. A transverse surface of the retainerextends across the passage and blocks the valve chamber to keep the ballvalve therewithin.

In operation, the ball valve is normally maintained in an open positionpermitting flow of high temperature air from the compression chamber tothe firing chamber formed in the illustrative embodiment by a fifth partof the passage and of enlarged size so as to receive the propellant andpermit the retainer and the valve to be inserted and removed through thefiring chamber end of the passage. When the pressure in the firingchamber, including passage means 52 and valve chamber 44, exceeds thepressure in the compression chamber, the ball valve is moved onto theconical seat to close the firing chamber relative to the compressionchamber and to provide a rigid reaction wall across the flow passage.

While the illustrative embodiment of the inventive principleshereinbefore disclosed has particular advantages, it will be recognizedthat certain details of construction may be modified and varied withoutdeparting from the fair meaning and intended scope of the claims.

We claim:

*1. In an air ignition system firearm such as a rifle or pistol having afiring chamber for ignition ofa propellant by surface contact with hightemperature air and a compression chamber for obtaining air at atemperature at which the propellant is ignitable, air passage meansconnecting said firing chamber to said compression chamber, a valve seatformed in said air passage means, an enlarged valve chamber formed insaid air passage means adjacent said valve seat, a ball valve smallerthan said valve chamber floatingly supported in said valve chamber, andvalve retainer means mounted in said air passage means adjacent saidvalve chamber and floatingly retaining said valvein said valve chamber,said valve being freely movable in said valve chamber solely in responseto pressure differentials existing between said firing chamber and saidcompression chamber and being movable by gas pressure in said firingchamber onto said valve seat to close said air passage means when thepressure in said firing chamber ex ceeds the pressure in saidcompression chamber, said valve retainer means comprising a one-piececoiled polygonal sheet of resilient material mounted in a cylindricalportion of said air passage means.

2. In an air ignition system firearm such as a rifle or pistol forfiring a round of ammunition having a projectile and a propellantignitable by surface contact with high temperature air:

ammunition holding means in the firearm for holding a round ofammunition in a firing position;

firing chamber forming means in the firearm adapted to be I associatedwith said round of ammunition in the firing position and to form afiring chamber about the propellant;

an air compression chamber in the firearm for obtaining high temperatureair for ignition of the propellant;

a passage in the firearm having a longitudinally extending central axisconnecting said air compression chamber to said firing chamber;

a first part of said passage adjacent said compression chamber having aperimeter of reduced size relative to the remainder of said passage;

a second part of said passage next adjacent said first part being ofoutwardly diverging generally conical shape and forming a valve seatfacing the firing chamber;

a third part of said passage next adjacent said valve seat having aperimeter of enlarged size relative to said first part and to said valveseat and forming a valve chamber;

a valve having a perimeter of reduced size relative to said third partand of enlarged size relative to said first part and being:

freely floatingly received in said valve chamber and freely movable awayfrom said valve seat to open said passage and permit flow of hightemperature air from the compression chamber to the firing chamber, andfreely movable onto said valve seat to close said passage after deliveryof high temperature air to the firing chamber to prevent flow ofpropellant gases from the firing chamber to the compression chamber,said movement being caused solely by pressure differential between thefiring chamber and the compression chamber;

a fourth part of said passage next adjacent said valve chamber having aperimeter of enlarged size relative to said valve to permit insertion ofsaid valve through said fourth part of said passage and providing valveretainer holding means between said valve chamber and said firingchamber, and a valve retainer member mounted in said fourth part of saidpassage on said valve retainer holding means along the wall of saidfourth part of the passage and defining therewith an opening connectingsaid valve chamber to said firing chamber, said retainer member having atransverse surface extending across said passage and blocking theadjacent end of said valve chamber to freely floatingly retain saidvalve in said valve chamber, said retainer member comprises a one-piececoiled polygonal sheet of resilient material having a widthsubstantially equal to the length of the fourth part of the passage.

3. In an air ignition system firearm, such as a rifle or pistol, havingan air compression cylinder means in which air is compressed to atemperature sufficient to ignite ammunition propellant by surfacecontact therewith, a barrel means through which an ammunition projectileis propelled after ignition of ammunition propellant associatedtherewith, and valve means between the cylinder means and the barrelmeans to prevent rearward flow ofpropellant gases, the improvementcomprising:

a separate one-piece valve plug mounted on said cylinder means;

a portion of said valve plug extending beyond said cylinder means towardsaid barrel means;

a firing chamber provided at the barrel end of said valve valve retainerholding means provided in said valve plug next adjacent said firingchamber;

a retainer mounted in said valve retainer holding means, a valve chamberprovided in said separate valve plug next adjacent said valve retainerholding means;

a free floating valve mounted in said valve chamber and having a sizesmaller than said valve retainer holding means and said valve chamber soas to be insertable therethrough;

a valve seat of smaller size than said valve in said separate valve plugnext adjacent said valve chamber and facing said barrel means;

an air passage in said separate valve plug connecting said cylindermeans to said firing chamber means through said valve seat;

a first valve plug chamber in said air cylinder means next adjacent andopening toward said barrel means, a second valve plug chamber in saidair cylinder means next adjacent and being smaller in size than saidfirst valve plug chamber;

a transverse abutment surface connecting said first valve plug chamberand said second valve plug chamber and facing said barrel means;

a first peripheralplug surface corresponding in size and shape to saidfirst valve plug chamber; and

a second peripheral plug surface corresponding in size and shape to saidsecond valve plug chamber, a transverse abutment surface on said valveplug corresponding in size and shape to said transverse abutment surfaceconnecting the valve plug chambers, and said separate valve plug beingsupportingly mounted in the valve plug chambers with the transverseabutment surfaces in engagement and holding said valve plug againstaxially directed forces generated by propellant gases in said firingchamber.

